Crossing the quantum street

For all that I know the Universe is under no obligation to make intuitive sense, I still don't like quantum mechanics. Just because something doesn't have to make sense doesn't mean we shouldn't try to make sense of it. I do not understand all of what Fuchs is saying here, but I'm inclined to like it.

The Many Worlds Interpretation just boils down to this: Whenever a coin is tossed (or any process occurs) the world splits. But who would know the difference if that were not true? What does this vision have to do with any of the details of physics? Who could take the many-worlds idea and derive any of the structure of quantum theory out of it? This would be a bit like trying to regrow a lizard from the tip of its chopped-off tail: The Everettian conception never purported to be more than a reaction to the formalism in the first place. 

An interpretation is powerful if it gives guidance, and I would say the very best interpretation is the one whose story is so powerful it gives rise to the mathematical formalism itself (the part where non-thinking can take over). The “interpretation” should come first; the mathematics (i.e., the pre-existing, universally recognized thing everyone thought they were talking about before an interpretation) should be secondary.

Exactly. It's not only equations that lead to predictions. Though for me, having a conceptual model I can intuitively understand is a worthy goal in itself; if it happens to also have other benefits, then so much the better. And from a moral perspective :

The Many Worlds Interpretation has always seemed to me as more of a comforting religion than anything else. It takes away human responsibility for anything happening in the world in the same way that a completely fatalistic, deterministic universe does, though it purportedly saves the appearance of quantum physics by having indeterministic chance in the branches.

Good point. If Many Worlds is correct then all our choices are meaningless. If the Universe is deterministic then we can't even make any choices, they are just illusionary. Both of these seem ridiculous to me : what's wrong the notion that there's one reality and we have free will ? Why is that so absurd ? What is there that needs to be explained away ?

Finally, on crossing the street :

In QBism, an agent—an observer—has some beliefs about the consequences of her actions on a physical system (or, again in less preferred language, “a measurement outcome”). She takes some action on the system and notes the consequence. That might well cause her to reevaluate her beliefs about the consequences of any future action she might take on it. Those reevaluated beliefs just are the new quantum state assignment. That’s all that “collapse” is: It is a change of one’s expectations based upon one’s lived experience. And if that’s all there is to it; collapse is no big deal.

Well I mean it's nice and all that observations just change the observer, not the whole Universe, but I don't see how that helps with the double slit experiment. I already know what happens to me; what I want to know is, what happens to that bloody electron ?

Quantum Physics is No More Mysterious Than Crossing the Street: A Conversation with Chris Fuchs

Recently, physicist Sean Carroll made my head spin with his explanation of the Many Worlds Interpretation of quantum mechanics. In this view, the world around us is just one version of many, many possible realities. Each time an event occurs with more than one possible outcome, reality splits into different versions.